A Study of Imatinib and Nilotinib in Patients With Chronic Myelogenous Leukemia in Chronic Phase

Key Inclusion Criteria 1. Patient is currently on treatment in the core study CAMN107ECN02 2. Patient who continues to derive benefit more than risk from the study treatment he/she takes in CAMN107ECN02, in the opinion of the investigator at the end of the study 3. Written informed consent must be obtained prior to enrolling in the extension study Key Exclusion Criteria: 1. Progression to CML-AP or BC 2. Patient whose treatment assigned in CAMN107ECN02 is not appropriate any longer, per investigator's assessment. 3. History of non-compliance to medical regimens, or patients who are considered potentially unreliable and/or not cooperative. 4. Women who are (a) pregnant and(b) women of child-bearing potential, defined as all women physiologically capable of becoming pregnant, unless they are using highly effective methods of contraception during dosing and at least 14 days after last dose of study medication. Highly effective contraception methods include: * Total abstinence (when this is in line with the preferred and usual lifestyle of the subject. Periodic abstinence (e.g., calendar, ovulation, symptothermal, post-ovulation methods) and withdrawal are not acceptable methods of contraception * Female sterilization (have had surgical bilateral oophorectomy with or without hysterectomy) or tubal ligation at least six weeks before taking study treatment. In case of oophorectomy alone, only when the reproductive status of the woman has been confirmed by follow up hormone level assessment * Male sterilization (at least 6 months prior to screening). For female subjects on the study the vasectomized male partner should be the sole partner for that subject. * Combination of any two of the following (a+b or a+c, or b+c): 1. Use of oral, injected or implanted hormonal methods of contraception or other forms of hormonal contraception that have comparable efficacy (failure rate \<1%), for example hormone vaginal ring or transdermal hormone contraception. 2. Placement of an intrauterine device (IUD) or intrauterine system (IUS) 3. Barrier methods of contraception: Condom or Occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/vaginal suppository In case of use of oral contraception women should have been stable on the same pill for a minimum of 3 months before taking study treatment.